Information scrambling and redistribution of quantum correlations through dynamical evolution in spin chains

TL;DR

This paper studies how quantum correlations spread in spin chains during dynamical evolution, revealing differences between spin-conserving and non-conserving models in terms of correlation propagation and information scrambling.

Contribution

It compares correlation spreading and information scrambling in various spin models, highlighting the role of conservation laws and integrability.

Findings

Correlations spread in spin-conserving models with nonnegative tripartite mutual information.

Non-conserving models show no correlation propagation and negative tripartite mutual information.

Spin-conserving dynamics lead to effective information scrambling, unlike non-conserving cases.

Abstract

We investigate the propagation of local bipartite quantum correlations, along with the tripartite mutual information to characterize the information scrambling through dynamical evolution of spin chains. Starting from an initial state with the first pair of spins in a Bell state, we study how quantum correlations spread to other parts of the system, using different representative spin Hamiltonians, viz. the Heisenberg Model, a spin-conserving model, the transverse-field XY model, a non-conserving but integrable model, and the kicked Harper model, a spin conserving but nonintegrable model. We show that the local correlations spread consistently in the case of spin-conserving dynamics in both integrable and nonintegrable cases, with a strictly nonnegative tripartite mutual information. In contrast, in the case of non-conserving dynamics, tripartite mutual information is negative and local pair correlations do not propagate.